The objectives of this study are to provide new knowledge about the risk of second primary lung cancer due to radiation and chemotherapy for breast cancer and Hodgkin's disease, and to quantify risk among longterm survivors. Histopathologic material for molecular analyses and diagnostic confirmation will also be collected. Overall it is envisioned that rosters of patients with breast cancer or Hodgkin's disease will undergo computer linkage with registry reports of second primary lung cancers. Detailed information on initial and subsequent courses of therapy will be abstracted for patients who developed subsequent lung cancer and a matched control group without second primary cancers.